A heavy oil catalytic cracking feed atomizing nozzle

Abstract

The application discloses a heavy oil catalytic cracking feed atomizing nozzle, which comprises a steam cavity, a premixing cavity, a Venturi tube and a nozzle opening which are sequentially communicated and coaxially arranged, the steam cavity is communicated with a steam inlet, a fixed plate is arranged between the steam cavity and the premixing cavity, a plurality of through holes are formed in the fixed plate, gas distribution pipes are fixedly connected to the through holes, a tangential raw oil inlet is arranged outside the premixing cavity, a spiral plate is arranged in the premixing cavity along an axial direction, the gas distribution pipes penetrate through the spiral plate, and at least two of the gas distribution pipes extend to the end of a diameter expansion section of the Venturi tube. The heavy oil catalytic cracking feed atomizing nozzle can realize multi-stage atomization of heavy oil, effectively eliminate large-diameter liquid drops, obviously improve the size distribution of oil mist sprayed from the nozzle, and then improve the contact between the oil and the catalyst, and optimize the product distribution of catalytic cracking.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of catalytic cracking device, and particularly relates to a heavy oil catalytic cracking feed atomizing nozzle. BACKGROUND

[0002] The raw oil feed atomizing nozzle is an important equipment in the catalytic cracking device in the field of petroleum refining, which has the function of breaking and atomizing the raw oil into a large number of small droplets. The atomized raw oil droplets are sprayed into the catalytic cracking riser reactor to mix and react with the catalyst in the riser reactor. In the catalytic cracking (FCC) process, the performance of the feed nozzle plays an important role in the cracking reaction and product distribution. The well-atomized raw material can contact with the high-temperature catalyst to make the raw oil vaporize rapidly, reduce the formation of "wet catalyst" (unvaporized oil adhering to the surface of the catalyst), improve the product distribution, reduce the coking phenomenon in the catalytic cracking reaction system, and bring considerable economic benefits.

[0003] At present, the catalytic cracking feed nozzle is generally divided into the following types: 1. Throat type atomizing nozzle, which uses the contraction-expansion type throat to increase the relative speed of gas and liquid, and relies on the speed difference of the gas-liquid two-phase to realize the atomization of the raw material; 2. Target type nozzle, in which the raw material vertically impacts the metal target under high pressure, and then performs the first atomization with the transverse gas flow to form a gas-liquid two-phase flow, which is accelerated at the nozzle outlet to realize the second atomization. This nozzle has good atomization effect, but requires high feed pressure and more atomizing medium, has high energy consumption, and has high equipment and operation cost; 3. Cyclone type nozzle, in which the gas-liquid mixture is rapidly rotated in the gas-liquid two-phase cyclone to realize the first atomization, and then realizes the second atomization at the nozzle outlet; 4. Bubble atomizing nozzle, in which high-pressure atomizing steam is injected into the flowing raw oil through multiple small holes to make the raw material contain a large number of bubbles, form a uniform bubble flow, use the bubble as power, and realize the atomization of the raw material by the generation, movement and deformation of the bubble until it is sprayed out of the nozzle outlet and the bubble bursts. The above types of nozzles have problems such as large atomized particle size, large spraying speed, uneven atomization, and high energy consumption.

[0004] Patent 201610537088.X discloses a catalytic raw oil pretreatment method, which disperses emulsified water into raw oil through an emulsifying tube (pore diameter of 1-60000 nm) to perform water-in-oil emulsification, so that the particle size of the oil droplets in the obtained emulsified raw oil is less than 50 microns, and then the emulsified raw oil is sprayed out of the nozzle. This method can effectively atomize the raw oil. However, this method increases the use of emulsified water, which in turn increases the water content entering the riser reactor, causing hydrothermal deactivation of the catalytic cracking catalyst, which is not conducive to the catalytic cracking reaction. Moreover, this patent increases the pretreatment process of the raw oil, which increases the equipment investment.

[0005] Based on the above problems, the present application provides a heavy oil feeding atomizing nozzle to solve the problems of large atomized particle size, uneven atomization, large ejection speed, high energy consumption and the like of the existing nozzle. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide a heavy oil catalytic cracking feeding atomizing nozzle, which can realize multi-stage atomization of raw oil, effectively eliminate large-diameter liquid droplets, and significantly improve the size distribution of raw oil droplets sprayed from the nozzle, thereby improving the contact between raw oil and catalyst and optimizing the product distribution of catalytic cracking.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] A heavy oil catalytic cracking feeding atomizing nozzle, the atomizing nozzle comprising a steam cavity, a premixing cavity, a Venturi tube and a nozzle opening which are sequentially communicated and coaxially arranged, the steam cavity being in communication with a atomizing steam inlet, a fixed plate being arranged between the steam cavity and the premixing cavity, a plurality of through holes being formed in the fixed plate, a gas distribution pipe being fixedly connected to the through holes, a tangential raw oil inlet being arranged on the outer side of the premixing cavity, a spiral plate being arranged in the premixing cavity along the axial direction, the gas distribution pipe penetrating through the spiral plate, and at least two of the gas distribution pipes extending to the end of the enlarged diameter section of the Venturi tube.

[0009] Preferably, the included angle between the spiral plate and the axis of the premixing cavity is β, and β = 5°-60°.

[0010] Preferably, the Venturi tube is composed of a reduced diameter section, a straight tube section and an enlarged diameter section from right to left, and the taper of the enlarged diameter section and the reduced diameter section is 4°-15°.

[0011] Preferably, the raw oil inlet is circular or rectangular, and the included angle between the raw oil inlet and the axis of the premixing cavity is α, and α = 30°-90°.

[0012] Preferably, the starting position of the spiral plate is arranged at the front end of the raw oil inlet, and the terminal position is arranged at the end of the gas distribution pipe away from the fixed plate; the rotation direction of the spiral plate is consistent with the direction of the raw oil flowing into the premixing cavity and then flowing to the Venturi tube, and a plurality of balance holes are arranged on the spiral plate.

[0013] Preferably, the gas distribution pipe is a microporous pipe, the pore diameter of the microporous pipe is 100-1000 μm, and the wall thickness of the microporous pipe is 5-20 mm.

[0014] Preferably, the cavity between the nozzle opening and the enlarged diameter section forms a remixing chamber.

[0015] The present application also protects the application of the heavy oil catalytic cracking feeding atomizing nozzle in heavy oil catalytic cracking.

[0016] Compared with the prior art, the present application has the following beneficial effects:

[0017] (1) The heavy oil catalytic cracking feed atomizing nozzle provided by the present application, through the arrangement of the gas distribution pipe and the spiral plate in the premixing chamber, makes the micro-nano bubbles quickly and uniformly dispersed into the raw oil, the raw oil is quickly and uniformly mixed with the atomizing steam, the gas-liquid mixture uniformly dispersed with the atomizing steam enters the converging section, the straight pipe section and the diverging section of the Venturi tube, and the gas-liquid two phases are uniformly mixed again, and then sprayed from the nozzle after the re-mixing chamber. The comprehensive effect of the gas distribution pipe, the spiral plate, the Venturi tube and the re-mixing chamber greatly enhances the atomizing effect of the nozzle, and the out-mist particle size (Sauter mean diameter and mass median diameter) of the raw oil is about 30 μm.

[0018] (2) The heavy oil catalytic cracking feed atomizing nozzle provided by the present application, through the tangential raw oil inlet and the spiral plate, the raw oil spirally enters the premixing chamber, and the raw oil is subjected to the action of its own surface tension and external force. When the flow rate of the raw oil reaches a certain value, the external force acting on the raw oil is greater than the surface tension, so that a large number of liquid droplets are thrown out from the spiral plate and the periphery of the raw oil main body, realizing the primary dispersion of the raw oil. Through the arrangement of the gas distribution pipe and the spiral plate, small gas bubbles of micro-nano level are vertically injected into the raw oil, impacting the raw oil and realizing the secondary dispersion of the raw oil. The raw oil uniformly dispersed with the small gas bubbles enters the converging section, and as the bubbles flow into the converging section, the gas-liquid two-phase velocity increases, and the spiral effect increases. Under the action of the spiral effect, the raw oil is spread into a film, increasing the surface area of the raw oil, and realizing the tertiary dispersion of the raw oil. The gas-liquid mixture continues to flow forward, and in the straight pipe section, due to the difference in gas-liquid two-phase velocity, the atomizing steam produces strong tearing and shearing action on the raw oil, realizing the quaternary dispersion of the raw oil. At the same time, when the gas-liquid mixture passes through the straight pipe section, the atomizing steam is compressed, and when the atomizing steam flows from the straight pipe section into the diverging section, the atomizing steam expands in volume, extruding the raw oil and again increasing the dispersion effect of the atomizing steam on the raw oil. After the gas-liquid mixture flows out of the diverging section, it enters the re-mixing chamber for mixing, and after the gas-liquid mixture is uniformly mixed, it is sprayed out of the nozzle through the nozzle outlet. Since the external environmental pressure of the nozzle is lower than the internal pressure of the nozzle, the small gas bubble atomizing steam rapidly expands and breaks at the nozzle outlet, breaking the raw oil into droplets, realizing the quinary dispersion of the raw oil, and atomizing the raw oil. At the same time, the gas distribution pipe extending through the converging section, the straight pipe section and the diverging section of the Venturi tube continuously supplies gas, accelerating the gas-liquid mixing rate in the converging section, and making the dispersion of the raw oil more uniform. After five times of dispersion and mixing, the size distribution of the raw oil mist is obviously improved, which in turn improves the contact between the raw oil and the catalyst and optimizes the product distribution of the catalytic cracking.

[0019] (3) The heavy oil catalytic cracking feed atomizing nozzle provided by the application is characterized in that raw oil enters a premixing cavity through a raw oil inlet and a spiral plate, and atomizing steam enters the premixing cavity through a gas distribution pipe, the spiral plate is arranged to make the raw oil move tangentially along a straight section and perpendicularly to the direction of the atomizing steam from the gas distribution pipe, the perpendicular cutting of the raw oil on the atomizing steam promotes the formation of micro-nano small bubbles, and then makes the atomizing steam uniformly and rapidly dispersed in the raw oil; at the same time, the arrangement of the spiral plate increases the movement track of the gas-liquid mixture in the premixing cavity, and then increases the residence time of the gas-liquid mixture in the premixing cavity, which is beneficial to the sufficient mixing of the atomizing steam and the raw oil in the premixing cavity, and the arrangement of the spiral plate increases the disturbance between the gas-liquid mixture, which is beneficial to the mixing between the atomizing steam and the raw oil, and is beneficial to the more uniform dispersion of the small bubbles into the raw oil to form a uniform bubble flow.

[0020] (4) The heavy oil catalytic cracking feed atomizing nozzle provided by the application is characterized in that the arrangement of the porous pipe and the spiral plate makes a large number of micro-nano small bubbles rapidly and uniformly dispersed into the raw oil, the formation of the micro-nano bubbles increases the bubble quantity of the atomizing steam of the same volume, increases the surface area of the atomizing steam, and increases the gas-liquid contact area, thereby enhancing the shearing action of the atomizing steam on the raw oil and the impact action of the atomizing steam explosion on the raw oil, and strengthening the atomizing effect of the nozzle.

[0021] (5) The heavy oil catalytic cracking feed atomizing nozzle provided by the application is characterized in that, due to the formation of the micro-nano bubbles and the uniform mixing of the micro-nano bubbles and the raw oil, the effect of the atomizing steam of the same volume is more obvious, so the consumption of the atomizing steam can be appropriately reduced, and then the ejection speed of the raw oil is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a structural schematic diagram of the heavy oil catalytic cracking feed atomizing nozzle of the application;

[0023] Figure 2 is a tangential raw oil inlet schematic diagram of the application;

[0024] Figure 3 is an oblique raw oil inlet schematic diagram of the application;

[0025] Figure 4 is a structural schematic diagram of the gas distribution pipe and the spiral plate inside the gas-liquid mixing chamber of the application;

[0026] Among them, 1, nozzle; 2, remixing chamber; 3, venturi; 4, diameter expansion section; 5, straight pipe section; 6, diameter reduction section; 7, gas distribution pipe; 8, premixing cavity; 9, raw oil inlet; 10, fixed plate; 11, spiral plate; 12, atomizing steam inlet; 13, steam cavity. DETAILED DESCRIPTION

[0027] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0029] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0030] In the description of the present application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, which is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0031] In addition, if the terms "first", "second" and the like appear, they are only used for differentiation description, and cannot be understood as indicating or implying relative importance.

[0032] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0033] As shown in Figure 1 and Figure 4 A heavy oil catalytic cracking feed atomizing nozzle, the atomizing nozzle comprises steam cavity 13, premixing cavity 8, Venturi tube 3 and nozzle 1 which are sequentially communicated and coaxially arranged, the steam cavity 13 is communicated with atomizing steam inlet 12, the fixed plate 10 is arranged between the steam cavity 13 and the premixing cavity 8, a plurality of through holes are formed in the fixed plate 10, the gas distribution pipe 7 is fixedly connected on the through holes, the tangential raw oil inlet 9 is arranged on the outside of the premixing cavity 8, the helical plate 11 is arranged in the premixing cavity 8 along the axial direction, the gas distribution pipe 7 penetrates the helical plate 11, and at least two of the gas distribution pipes 7 extend to the end of the diameter expansion section 4 of the Venturi tube 3.

[0034] In some embodiments, the included angle between the spiral plate 11 and the axis of the premixing cavity 8 is set as β, and β = 5°-60°, which can be 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, preferably 45°.

[0035] Specifically, the spiral plate is arranged, the gas-liquid mixture enters the reduced diameter section to continue the spiral movement, and due to the decrease of the movement cross-sectional area, the gas-liquid two-phase velocity increases, the spiral effect increases, and under the spiral effect, the raw oil is spread into a film, the surface area of the raw oil is increased, and the atomization quality of the raw oil is enhanced.

[0036] In some embodiments, the Venturi tube 3 is composed of the reduced diameter section 6, the straight tube section 5 and the expanded diameter section 4 from right to left in sequence, the taper of the expanded diameter section 4 and the reduced diameter section 6 is 4°-15°, which can be 4°, 5°, 6°, 7°, 8°, 9°, 10°, 11°, 12°, 13°, 14°, 15°, preferably 7°.

[0037] In some embodiments, as shown in Figure 2 , Figure 3 The included angle between the raw oil inlet 9 and the axis of the premixing cavity 8 is set as α, and α = 30°-90°, which can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, preferably 45°.

[0038] In some embodiments, as shown in Figure 4 The starting position of the spiral plate 11 is arranged at the front end of the raw oil inlet 9, and the terminal position is arranged at the end of the gas distribution pipe 7 away from the fixed plate 10; the rotation direction of the spiral plate 11 is consistent with the direction of the raw oil flowing into the premixing cavity 8 to the Venturi tube 3, and the spiral plate 11 is provided with a plurality of balance holes.

[0039] In some embodiments, the gas distribution pipe 7 is a microporous pipe, which can be one of a sintered metal powder microporous pipe or a ceramic powder sintered pipe.

[0040] Specifically, the microporous pipe arranged can form micro-nano small bubbles in the atomized steam entering the premixing cavity, and then the atomized steam is uniformly and rapidly dispersed in the raw oil.

[0041] In some embodiments, the micropore diameter of the microporous tube is 100-1000 μm, which can be 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, 500 μm, 550 μm, 600 μm, 650 μm, 700 μm, 750 μm, 800 μm, 850 μm, 900 μm, 950 μm, 1000 μm, preferably 200 μm; the tube wall thickness of the microporous tube is 5-20 mm, which can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 12 mm, 14 mm, 16 mm, 18 mm, 20 mm, preferably 10 mm.

[0042] In some embodiments, the cavity between the nozzle 1 and the diameter expansion section 4 forms a remixing chamber 12.

[0043] The fixed connection described in the present application can be welding, threaded connection or flange connection, etc.

[0044] The working principle of the heavy oil catalytic cracking feed atomizing nozzle provided by the present application is as follows: the raw oil enters the premixing chamber 8 through the raw oil inlet 9 and the spiral plate 11, and the raw oil performs spiral motion, and a large number of liquid droplets are thrown out from the spiral plate 11 and the periphery of the raw oil body, so that the raw oil is dispersed once. The atomizing steam enters the raw oil vertically after forming micro-nano small bubbles through the atomizing steam inlet 12, the gas distribution pipe 7 and the spiral plate 11, so as to impact the raw oil and realize the secondary dispersion of the raw oil. At the same time, the micro-nano holes on the gas distribution pipe 7 and the spiral plate 11 promote the formation of micro-nano small bubbles, and the spiral plate 11 in the premixing chamber 8 makes the small bubbles uniformly and quickly dispersed into the raw oil. The gas-liquid mixture is spirally mixed in the premixing chamber 8, and the small bubbles uniformly enter the raw oil, and then the gas-liquid mixture uniformly enters the diameter reduction section 6, the speed of the gas-liquid two phases increases, and the spiral effect increases, so that the raw oil is spread into a film under the action of the spiral effect, the surface area of the raw oil is increased, and the raw oil is dispersed three times. Subsequently, the gas-liquid mixture enters the straight pipe section 5, at which the gas-liquid two phases move at high speed, and the speed difference between the gas-liquid two phases makes the raw oil broken into small liquid droplets by the atomizing steam, forming a gas-liquid two-phase atomized flow, and realizing the fourth dispersion of the raw oil; and since the gas distribution pipe 7 extends to the end of the diameter expansion section, the gas distribution pipe continuously supplies gas during the dispersion of the gas-liquid two phases, so as to ensure the mixing efficiency and uniformity of the gas-liquid two phases in the Venturi tube, and make the gas more uniformly dispersed in the raw oil; the gas-liquid two-phase atomized flow enters the remixing chamber 2 through the diameter expansion section 4, the gas-liquid mixture is mixed uniformly again, and then is sprayed out of the nozzle through the nozzle 1, the small bubbles mixed in the raw oil rapidly expand and break at the nozzle 1 to break the raw oil into liquid droplets, realizing the fifth dispersion, and the raw oil is atomized.

[0045] Example 1

[0046] AsFigure 1 The application discloses a heavy oil catalytic cracking feed atomizing nozzle, which comprises a steam cavity 13, a premixing cavity 8, a Venturi tube 3 and a nozzle 1 which are sequentially communicated and coaxially arranged, the steam cavity 13 is communicated with a steam inlet 12, a fixed plate 10 is arranged between the steam cavity 13 and the premixing cavity 8, a plurality of through holes are formed in the fixed plate 10, and gas distribution pipes 7 are fixedly connected to the through holes, a tangential raw oil inlet 9 is arranged on the outer side of the premixing cavity 8, a spiral plate 11 is arranged in the premixing cavity 8 along the axial direction, the gas distribution pipes 7 penetrate through the spiral plate 11, four gas distribution pipes 7 extend to the end of a diameter expansion section 4 of the Venturi tube 3, and the other gas distribution pipes 7 extend to the front end of a diameter reduction section 6 of the Venturi tube 3.

[0047] In the embodiment, the included angle between the spiral plate 11 and the axis of the premixing cavity 8 is β, and β = 45°.

[0048] In the embodiment, the nozzle 1 is provided with a plurality of gas distribution pipes 7. Figure 3 The Venturi tube 3 is sequentially composed of the diameter reduction section 6, a straight pipe section 5 and the diameter expansion section 4 from right to left, and the taper of the diameter expansion section 4 and the diameter reduction section 6 is 10°.

[0049] In the embodiment, the raw oil inlet 9 is circular, and the included angle between the raw oil inlet 9 and the axis of the premixing cavity 8 is α, and α = 45°.

[0050] In the embodiment, the starting position of the spiral plate 11 is arranged at the front end of the raw oil inlet 9, and the ending position is arranged at the end of the gas distribution pipe 7 away from the fixed plate 10; the rotating direction of the spiral plate 11 is consistent with the direction of the raw oil flowing into the premixing cavity 8 and then flowing to the Venturi tube 3, and a plurality of balance holes are arranged on the spiral plate 11.

[0051] In the embodiment, the gas distribution pipe 7 is a microporous pipe, and the microporous pipe is a sintered metal powder microporous pipe.

[0052] In the embodiment, the pore diameter of the microporous pipe is 200 μm, and the pipe wall thickness of the microporous pipe is 10 mm.

[0053] In the embodiment, the opening shape of the nozzle 1 is strip-shaped.

[0054] In the embodiment, the cavity between the nozzle 1 and the diameter expansion section 4 forms a remixing chamber 12.

[0055] In the embodiment, the fixed connection is welding.

[0056] The nozzle described in the above examples is applied in a 1.8 million tons / year catalytic cracking unit, a single nozzle handles 35 t / h, the preheating temperature of heavy oil (atmospheric residue) is 180°C, the heavy oil inlet pressure is 0.6 MPa, the atomizing steam consumption is 1400 kg / h, the atomizing steam inlet pressure is 0.7 MPa, the catalytic cracking reactor temperature is 550°C, the pressure is 0.2 MPa, the heavy oil out-mist particle size is about 30 μm, the contact between heavy oil and catalyst is improved, and the product distribution of catalytic cracking is optimized.

[0057] While embodiments of the present application have been shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details can be made therein without departing from the spirit and scope of the application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A heavy oil catalytic cracking feed atomizing nozzle characterized by, The atomizing nozzle comprises a steam cavity (13), a premixing cavity (8), a Venturi tube (3) and a nozzle (1) which are sequentially communicated and coaxially arranged, the steam cavity (13) is communicated with a atomizing steam inlet (12), a fixed plate (10) is arranged between the steam cavity (13) and the premixing cavity (8), a plurality of through holes are formed in the fixed plate (10), a gas distribution pipe (7) is fixedly connected to the through holes, a tangential raw oil inlet (9) is arranged outside the premixing cavity (8), a spiral plate (11) is arranged in the premixing cavity (8) along the axial direction, and the gas distribution pipe (7) penetrates the spiral plate (11), and at least two of the gas distribution pipes (7) extend to the end of the expansion section (4) of the Venturi tube (3). The starting position of the spiral plate (11) is arranged at the front end of the raw oil inlet (9), and the ending position is arranged at the end of the gas distribution pipe (7) away from the fixed plate (10), the rotation direction of the spiral plate (11) is consistent with the direction of the raw oil flowing into the premixing cavity (8) and then flowing to the Venturi tube (3), and a plurality of balance holes are arranged on the spiral plate (11). The gas distribution pipe (7) is a microporous pipe, the pore diameter of the microporous pipe is 100-1000 μm, and the wall thickness of the microporous pipe is 5-20 mm.

2. A heavy oil catalytic cracking feed atomizing nozzle according to claim 1, characterized in that, The included angle between the spiral plate (11) and the axis of the premixing cavity (8) is β, and β=5°-60°.

3. A heavy oil catalytic cracking feed atomizing nozzle according to claim 1, characterized in that, The Venturi tube (3) is composed of a reduced diameter section (6), a straight pipe section (5) and an expansion section (4) from right to left, and the taper of the expansion section (4) and the reduced diameter section (6) is 4°-15°.

4. A heavy oil catalytic cracking feed atomizing nozzle according to claim 1, characterized in that, The raw oil inlet (9) is circular or rectangular, and the included angle between the raw oil inlet (9) and the axis of the premixing cavity (8) is α, and α=30°-90°.

5. A heavy oil catalytic cracking feed atomizing nozzle according to claim 1 wherein, The cavity between the nozzle (1) and the expansion section (4) forms a remixing chamber (2).

6. Application of the heavy oil catalytic cracking feed atomizing nozzle according to any one of claims 1-5 in heavy oil catalytic cracking.

Images